Peatland fish of Sebangau, Borneo: diversity, monitoring and conservation

Tropical peat swamp forests provide important ecosystem services, ranging from carbon storage and fire prevention to fish provision. In the Sebangau catchment of Central Kalimantan, Indonesia, we completed the first detailed spatial and temporal assessments of local fish biodiversity in peat swamp forest and blackwater river habitats. Monthly environmental and fish data were collected over a 15-month period in both riverine and forest habitats. This resulted in a species list of 55 species from 16 different families. Species richness in the river was almost 1.5 times higher than in the forest, probably due to the sampling methods and trap selectivity. Average monthly river fish catches were negatively correlated with average monthly river depth. River fish surveys were conducted pre- and post- fire in 2015, with results showing increased river acidity and reduced fish catches post-fire. The fish and environmental data presented form a baseline for future monitoring projects and highlight a previously overlooked potential impact of fire on local biodiversity in Indonesia, namely that fire is likely to have negative impacts on the sizes of fish populations and catches. There are direct implications for human communities that depend on fishing for their livelihoods. Because peatlands and their rivers face continued human disturbance and degradation, assessments of fish biodiversity and water quality are of high priority.